#61 Allow data directive statements in Rexx files.

Sometimes it is nice to be able to include data
directly within a Rexx program without having to worry
about whether it is quoted properly or conforms to
valid Rexx syntax (such as help information).
Something similar to XML's CDATA tags would work quite
nicely:

::data foo
whatever I want to put here is fine....
on as many lines as I want!
::::data -- end of data marker....can be anything
"distinctive"

The data would be available in the local environment as
an array of lines, and should be scopeable with the
public keyword.